Enhanced intraocular lens for reducing glare

ABSTRACT

An intraocular lens implantable in an eye includes an optic for placement in the capsular bag of the eye and for directing light toward the retina of the eye. The optic has a central optical axis, an anterior face, an opposing posterior face and a peripheral edge between the faces. The peripheral edge has one or more curved or angled surfaces that reduce glare within the IOL. For instance, a rounded transition surface on the anterior side of the peripheral edge diffuses the intensity of reflected light, or a particular arrangement of straight edge surfaces refracts the light so as not to reflect, or does not reflect at all. The intersection of the peripheral edge and at least one of the anterior face and the posterior face, preferably both of such faces, forms a peripheral corner located at a discontinuity between the peripheral edge and the intersecting face or faces. The present IOLs inhibit cell growth from the eye in front of or in back of the optic and reduce glare obtained in the eye in which the IOL is located.

RELATED APPLICATION

The present application is a continuation-in-part of co-pendingapplication Ser. No. 10/245,920 filed Sep. 18, 2002, which is acontinuation of U.S. Ser. No. 09/507,602, filed Feb. 18, 2000, now U.S.patent No. 6,468,306,which is a continuation of application Ser. No.09/448,713, filed Nov. 24, 1999, now abandoned, which is acontinuation-in-part of application Ser. No. 09/086,882, filed May 29,1998, now U.S. Pat. No. 6,162,249, issued Dec. 19, 2000. The disclosureof each of these applications and the patent is incorporated in itsentirety by reference herein.

BACKGROUND OF THE INVENTION

This invention relates to intraocular lenses (IOLs) and, moreparticularly, to IOLs which inhibit migration or growth of cells fromthe eye onto the IOL and reduce glare in the eye.

An intraocular lens is commonly used to replace the natural lens of ahuman eye when warranted by medical conditions. It is common practice toimplant an IOL in a region of the eye known as the capsular bag orposterior capsule.

One potential concern with certain IOLs following implantation is thatcells from the eye, particularly epithelial cells from the capsular bag,tend to grow in front of and/or in back of the optic of the IOL. Thistends to block the optic of the IOL and to impair vision.

A common treatment for this condition is to use a laser to destroy thecells and a central region of the capsular bag. Although this treatmentis effective, the laser is expensive and is not available throughout theworld. There is also cost associated with the laser treatment as well assome patient inconvenience and risk of complications. Finally, the lasertreatment may affect the performance of some IOLs.

Another potential concern after certain IOLs are implanted has to dowith glare caused by light reflecting off of the IOLs, in particular,the edges of IOLs. Such glare can be an annoyance to the patient and mayeven lead to removal and replacement of the IOL.

It would be advantageous to provide IOLs which inhibit growth of cellsfrom the eye onto the IOLs and/or which reduce glare caused by the IOLsin the eye.

SUMMARY OF THE INVENTION

New IOLs have been discovered. Such IOLs are effective to inhibit cellgrowth, in particular epithelial cell growth, from the eye onto theoptic of the IOLs. The IOLs are structured so as to reduce glare, inparticular edge glare, in the eye resulting from the presence of theIOL. The present IOLs are straightforward in design and construction,are easily manufactured, can be implanted, or inserted in the eye usingconventional techniques, and are effective and produce substantialbenefits in use in the eye.

In one broad aspect of the present invention, the present IOLs areimplantable in the eye and comprise an optic having a central opticalaxis, an anterior face, an opposing posterior face and a peripheral edgeor edge surface between the faces. The optic is adapted for placement inthe capsular bag of the eye and for directing light toward the retina ofthe eye. In a very useful embodiment, the IOLs further comprise at leastone fixation member, preferably two fixation members, and morepreferably two elongated fixation members, coupled to the optic for usein fixing the IOLs in the eye.

In a preferred aspect, the present invention provides a reduced-glareintraocular lens implantable in the eye and including an optic adaptedfor placement in the capsular bag of the eye for directing light towardthe retina of the eye. The optic has a central optical axis, an anteriorface, an opposing posterior face, and a peripheral edge. The peripheraledge has a least one surface with a linear cross-sectional configurationthat is oriented other than parallel to the central optical axis.Further, the peripheral edge and the anterior face, and/or theperipheral edge and the posterior face, intersect to form at least oneperipheral edge corner located at a discontinuity between the peripheraledge and the intersecting anterior or posterior face. The peripheraledge may also include a rounded transition surface on its anterior side,wherein the peripheral edge corner is provided only between theperipheral edge and intersecting posterior face. The peripheral edge mayalso include two linear surfaces angled with respect to one another,wherein the other linear surface may be oriented parallel to the opticalaxis.

In another aspect of present invention, a reduced-glare intraocular lensimplantable in an eye comprises an optic adapted for placement in thecapsular bag of the eye and for directing light toward the retina of theeye. The optic has a central optical axis, an anterior face, and aposterior face. An outer edge of the optic is defined by a peripheraledge that includes, in cross-section, a linear surface that isnon-parallel with respect to the optical axis and a posterior cornerdefining the posterior limit of the peripheral edge. Advantageously,cell growth from the eye in front of or in back of the optic is moreinhibited relative to a substantially identical intraocular lens withoutthe posterior corner, and reduced glare is obtained in the eye relativeto a substantially identical intraocular lens having a peripheral linearsurface that is parallel to the central optical axis. The optic may alsoinclude a convex surface on the peripheral edge defining a transitionsurface between the anterior face and the linear surface. A secondlinear surface that is parallel with respect to the optical axis mayalso be provided. In addition, the optic may include first and secondlinear surfaces, wherein the first linear surface is anteriorly-facingand second linear surface is parallel with respect to the optical axis.

In still a further embodiment of the present invention, an intraocularlens implantable in an eye includes an optic adapted for placement inthe capsular bag of the eye and for directing light toward the retina ofthe eye. The optic includes a peripheral edge extending between ananterior face and a posterior face consisting only of a conical surface.The conical surface may be posteriorly-facing, wherein the conicalsurface is sufficiently angled with respect to the optical axis so as toincrease transmission of light from the optic through the conicalsurface relative to a substantially identical intraocular lens with aperipheral edge consisting only of a surface parallel to the opticalaxis. Alternatively, a peripheral land extends between the anterior faceand conical surface, wherein the conical surface is generallyposteriorly-facing and wherein the conical surface and the peripheralland adjacent the conical surface define an acute included angle. In astill further form, the conical surface may be anteriorly-facing,wherein the conical surface is sufficiently angled with respect to theoptical axis so as to decrease the probability of light internal to theoptic contacting the conical surface relative to a substantiallyidentical intraocular lens with a peripheral edge consisting only of asurface parallel to the optical axis.

Another aspect of present invention is an intraocular lens including anoptic defining a central optical axis, an anterior face, and a posteriorface. A peripheral edge extending between the anterior face and theposterior face includes, in cross-section, a linear edge surfaceterminating at its anterior side in an anterior edge corner. An anteriorland adjacent the anterior edge corner, wherein the linear edge surfaceand the anterior land define an acute included angle so as to increasetransmission of light from the optic through the conical surfacerelative to a substantially identical intraocular lens with a linearedge surface and anterior land that define an included angle of 90° ormore.

In a still further form, the present invention provides an intraocularlens having optic defining optical axis, an anterior face, and aposterior face. A peripheral edge stands between the anterior face andposterior face and includes, in cross-section, at least two linear edgesurfaces that are not parallel to the optical axis. The two linear edgesurfaces may be angled radially inwardly toward each other to meet anapex and together define a groove. Further, a plurality of such groovesmay be provided by adjoining linear edge surfaces. A rounded transitionsurface extending between an anteriorly-facing edge surface and theanterior face of the optic may also be provided.

The peripheral edge of the present IOLs may have a substantiallycontinuous curved configuration in the direction between the anteriorand posterior faces of the optic, that is between the faces in across-sectional plane including the optical axis. Indeed, the entireperipheral edge may have a substantially continuous curved configurationin the direction between the anterior and posterior faces of the optic.

The peripheral edge of the present IOLs may have a curved surface, aflat surface that is either parallel to the optical axis or not, or acombination of flat and/or curved surfaces. For example, if a portion ofthe peripheral edge has a substantially continuous curved configuration,another portion, for example, the remaining portion, of the peripheraledge preferably has a linear configuration in the direction between theanterior and posterior faces of the optic which is not parallel to theoptical axis.

The present IOLs preferably provide reduced glare in the eye relative tothe glare obtained with a substantially identical IOL having aperipheral edge parallel (flat) to the central optical axis in thedirection between the faces of the optic. One or more of at least partof the peripheral edge, a portion of the anterior face near theperipheral edge and a portion of the portion face near the peripheraledge may be at least partially opaque to the transmission of light,which opacity is effective in reducing glare. Such opacity can beachieved in any suitable manner, for example, by providing “frosting” orphysically or chemically roughening selected portions of the optic.

In addition, the intersection of the peripheral edge and at least one orboth of the anterior face and the posterior face forms a peripheralcorner or corner edge located at a discontinuity between the peripheraledge and the intersecting face. Such peripheral corner, which may beconsidered a sharp, abrupt or angled peripheral corner, is effective ininhibiting migration or growth of cells from the eye onto the IOL.Preferably, the present IOLs, with one or two such angled peripheralcorners, provide that cell growth from the eye in front of or in back ofthe optic is more inhibited relative to a substantially identical IOLwithout the sharp, abrupt or angled peripheral corner or corners.

The peripheral edge and the intersecting face or faces intersect at anangle or angles, preferably in a range of about 45° to about 135°, morepreferably in a range of about 60° to about 120°. In one embodiment, anobtuse angle (that is greater than 90° and less than 180°) ofintersection is provided. Such angles of intersection are very effectivein facilitating the inhibition of cell migration or growth onto and/orover the anterior face and/or posterior face of the optic of the presentIOL.

In one very useful embodiment, at least one, conceivably both, of theanterior face and the posterior face has a peripheral region extendingfrom the peripheral edge toward the central optical axis. The peripheralregion or regions preferably are substantially planar, and may or maynot be substantially perpendicular to the central optical axis.Preferably, only the anterior face has a peripheral region extendingfrom the peripheral edge toward the central optical axis which issubstantially planar, more preferably substantially perpendicular to thecentral optical axis. The peripheral region preferably has a radialdimension of at least about 0.1 mm, and more preferably no greater thanabout 2 mm.

The dimension of the optic parallel to the central optical axis betweenthe anterior face and the posterior face preferably is smaller at ornear the peripheral edge, for example, at the peripheral region orregions, than at the central optical axis.

In one embodiment, at least a part or a portion of the peripheral edgesurface of the optic is generally convex relative to the central opticalaxis. Alternately, at least a part or a portion of the peripheral edgesurface of the optic is generally concave relative to the centraloptical axis. In a particularly useful embodiment, a first portion ofthe peripheral edge surface is generally convex relative to the centraloptical axis and a second portion of the peripheral edge surface isgenerally concave relative to the optical axis.

Preferably, the peripheral edge and/or the peripheral region or regionscircumscribe the central optical axis. The anterior face and theposterior face preferably are both generally circular in configuration,although other configurations, such as oval, elliptical and the like,may be employed. At least one of the anterior and posterior faces has anadditional region, located radially inwardly of the peripheral region,which is other than substantially planar.

Each and every combination of two or more features described herein isincluded within the scope of the present invention provided that suchfeatures are not mutually inconsistent.

The invention, together with additional features and advantages thereof,may best be understood by reference to the following description takenin connection with the accompanying illustrative drawings in which likeparts bear like reference numerals.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of one form of intraocular lens (IOL) constructedin accordance with the teachings of present invention.

FIG. 2 is a cross-sectional view of an optic of a prior art IOL.

FIG. 3 is an elevational view of an optic of an exemplary embodiment ofan IOL of the present invention having a medium diopter value.

FIG. 4 is an elevational view of an optic of a further exemplary IOL ofthe present invention having a small diopter value.

FIG. 5 is an elevational view of an optic of a further exemplary IOL ofthe present invention having a large diopter value.

FIG. 6 is an elevational view of a peripheral edge region of the IOL ofFIG. 3 showing the paths of a plurality of light rays passingtherethrough.

FIG. 7 is a cross-sectional view of a peripheral edge region of an IOLof the present invention having an edge surface that is parallel to theoptical axis, an anteriorly-facing edge surface that is not parallel tothe optical axis and an anterior peripheral land that is perpendicularto the optical axis.

FIG. 8 is a cross-sectional view of a peripheral edge region of an IOLof the present invention having an anteriorly-facing edge surface notparallel to the optical axis and an anterior peripheral landperpendicular to the optical axis.

FIG. 9 is a cross-sectional view of a peripheral edge region of an IOLof the present invention having an anteriorly-facing edge surface thatis not parallel to the optical axis and no peripheral land.

FIG. 10 is a cross-sectional view of a peripheral edge region of an IOLof the present invention having an edge surface that is parallel to theoptical axis and an anterior peripheral land that is not perpendicularto the optical axis.

FIG. 11 is a cross-sectional view of a peripheral edge region of an IOLof the present invention having an edge surface that is parallel to theoptical axis, an anterior peripheral land that is perpendicular to theoptical axis, and an anterior peripheral land that is not perpendicularto the optical axis.

FIG. 12 is a cross-sectional view of a peripheral edge region of an IOLof the present invention having a posteriorly-facing edge surface thatis not parallel to the optical axis and no peripheral land.

FIG. 13 is a cross-sectional view of a peripheral edge region of an IOLof the present invention having a posteriorly-facing edge surface thatis not parallel to the optical axis and an anterior peripheral land thatis perpendicular to the optical axis.

FIG. 14 a is a radial sectional view of an IOL of the present inventionshowing a fixation member extending from a peripheral edge.

FIG. 14 b is an elevational view of a peripheral edge region of the IOLof FIG. 14 a.

FIGS. 15-17 are elevational views of peripheral edge regions of IOLs ofthe present invention each having an anteriorly-facing edge surface thatis not parallel to the optical axis, a rounded transition surfacebetween the edge surface and the anterior face of the IOL, and aposterior peripheral land.

FIG. 18 is an elevational view of a peripheral edge region of an IOL ofthe present invention having a baffle structure disposed along ananteriorly-facing edge surface.

FIG. 19 is an elevational view of a peripheral edge region of an IOL ofthe present invention having an anteriorly-facing edge surface and arounded transition surface between the edge surface and the anteriorface of the IOL.

FIG. 20 is an elevational view of a peripheral edge region of an IOL ofthe present invention having both anteriorly- and posteriorly-facingedge surfaces.

FIG. 21 is a cross-sectional view of the optic of an alternative IOL ofthe present invention.

FIG. 22 is a cross-sectional view of the optic of an alternateembodiment of an IOL in accordance with the present invention.

FIG. 23 is a partial cross-sectional view of the optic of a furtherembodiment of an IOL in accordance with the present invention.

FIG. 24 is a partial cross-sectional view of an additional embodiment ofan IOL in accordance with the present invention.

FIG. 25 is a partial cross-sectional view of the optic of anotherembodiment of an IOL in accordance with the present invention.

FIG. 26 is a partial cross-sectional view of the optic of a furtheralternate embodiment of an IOL in accordance with the present invention.

FIG. 27 is a partial cross-sectional view of the optic of a stillfurther embodiment of an IOL in accordance with the present invention.

FIG. 28 is a partial cross-sectional view of the optic of still anotherembodiment of an IOL in accordance with the present invention.

FIG. 29 a is a modeled ray tracing of the glare resulting from lightpassing through a first exemplary interocular lens of the presentinvention having peripheral rough surfaces over the entire optic portionexcept for the central optically refractive anterior and posteriorsurfaces.

FIG. 29 b is a modeled ray tracing of the glare resulting from lightpassing through a second exemplary interocular lens of the presentinvention similar to that modeled in FIG. 29 a.

FIG. 30 is a modeled ray tracing of the glare resulting from lightpassing through an interocular lens similar in shape to the lensesmodeled in FIGS. 29 a and 29 b, but without the extensive peripheralroughening.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows an IOL 20 which generally comprises an optic 22 andfixation members 24 a and 24 b. In this embodiment, the optic 22 may beconsidered as effective for focusing light on or near the retina of theeye. Optical axis 26 passes through the center of optic 22 in adirection generally transverse to the plane of the optic.

In this embodiment, the optic 22 is circular in plan and bi-convexapproaching the optical axis 26. However, this configuration is merelyillustrative as other configurations and shapes may be employed. Theoptic 22 may be constructed of any of the commonly employed materialsused for rigid optics, such as polymethylmethacrylate (PMMA), orcommonly employed materials used for resiliently deformable optics, suchas silicone polymeric materials, acrylic polymeric materials,hydrogel-forming polymeric materials, mixtures thereof and the like.

The fixation members 24 a and 24 b in this embodiment are generallyC-shaped and are integral with the optic 22. However, this is purelyillustrative of the fixation members 24 a and 24 b as the fixationmembers may be of other configurations and/or may be separate membersaffixed to the optic 22 in any of a variety of conventional ways. Statedanother way, the IOLs of the present invention may consist of one piece,with unitary optic and fixation members, or may be three or more pieces,with two or more fixation members connected to the optic. IOL 20 can beproduced using conventional techniques well-known in the art.

Unless expressly described hereinafter, the general structuralcharacteristics of IOL 20 apply to the other IOLs noted herein.

FIG. 2 illustrates an optic 30 of an IOL of the prior art having anoptical axis OA, a convex anterior face AF, a convex posterior face PF,and a peripheral edge 32. The peripheral edge 32 is typically circularand has a constant cross-section circumscribing the optic 30. The optic30 illustrated is of the square-cornered variety which provides someinhibition of cell growth onto the optic 30, a condition known asposterior capsule opacification (PCO). The peripheral edge 32 comprisesan edge surface 34 that is parallel to the optical axis OA, and bothanterior and posterior edge corners 36 a, 36 b, respectively. Inaddition, anterior and posterior lands 38 a, 38 b, extend between theanterior face AF and posterior face PF and respective edge corner 36 aor 36 b. Both the anterior and posterior lands 38 a, 38 b extendsubstantially perpendicularly with respect to the optical axis OA.Because of the parallel edge surface 34, the prior art optic 30 does notprovide reduced edge glare as do the IOLs in accordance with the presentinvention.

In the present application, the terms anterior and posterior are used intheir conventional sense; anterior refers to the front side of the eye,while posterior refers to the rear side. A number of surfaces of theintraocular lens of present invention are denoted either“anteriorly-facing” or “posteriorly-facing” to indicate theirorientation with respect to the optical axis of the lens. For purpose ofexplanation, a surface that is parallel to the optical axis is neitheranteriorly-facing or posteriorly-facing. A surface that is even slightlyangled in one direction or the other can be identified with either theanterior or posterior side of the lens, depending on which side thatsurface faces.

FIG. 3 illustrates an optic 40 of an IOL of the present invention havingan advantageous peripheral edge 42. The optic 40 defines an optical axisOA, a convex anterior face AF, and a convex posterior face PF. Theperipheral edge 42 is desirably circular in shape, and has a constantcross-section circumscribing the optic 40. However, it should beunderstood by those skilled in the art that the peripheral edge 42 maynot extend completely around the optic 40, and may be interrupted byalternative peripheral edge configurations, including combinations ofperipheral edge configurations in accordance with the present invention.

The optic 40 is shown in elevational view to better illustrate theperipheral edge 42 in relation to the convex anterior face AF andposterior face PF. On the anterior side, the peripheral edge 42 includesa curved or rounded transition surface 44 leading to an anteriorperipheral land or region 46 that is desirably linear and substantiallyperpendicular to the optical axis OA. On the posterior side, adiscontinuous posterior edge corner 50 separates the peripheral edge 42from the posterior face PF, with no peripheral land. The edge corner 50defines the posterior limit of the peripheral edge 42. The peripheraledge 42 further comprises an edge surface 52 that is linear andsubstantially parallel to the optical axis OA adjacent the posterioredge corner 50, and an anteriorly-facing edge surface 54 that is linearand non-parallel to the optical axis OA adjacent the rounded transitionsurface 44. A shallow corner or discontinuity 56 separates the paralleledge surface 52 from the non-parallel edge surface 54.

In this respect, the term discontinuity refers to a transition betweentwo peripheral edge surfaces that is visible as a corner or peripheralline on the optic. Of course, all corners ultimately have a radius, butdiscontinuity in this regard pertains only to a corner that is visibleas a discrete line as opposed to a more rounded region. In turn,“visible” in this regard refers to visible as seen by the naked eye, orwith the assistance of certain low-power magnification devices, such asan ocular. Another way to define corners in the presence sense is theintersection between two linear surfaces, at least with respect to themagnification shown in the drawings of the present application. Stillanother way to look at the effect of a discontinuity at the corner ofthe peripheral edge is that cell growth from the eye in front of or inback of the optic is more inhibited relative to a substantiallyidentical intraocular lens without the discontinuity.

As used herein, the term “linear,” used to refer to various edgesurfaces, is in all cases as viewed through the cross-section of theparticular edge. That is, the lenses of the present invention aregenerally circular, and the peripheral edges thus defined circularsurfaces of revolution. A linear cross-sectional edge can thereforedefined a cylinder, or a conical surface. If the edge is parallel to theoptical axis, the surface is cylindrical. On the other hand, if thesurface is non-parallel with respect to the optical axis, the surface isconical. Therefore, a linear, non-parallel edge surface is conical, atleast for a portion of the peripheral edge. It should be noted that, asmentioned above, the edge geometry around the periphery of anyparticular lens of the present invention may not be constant, and theedge surfaces disclosed herein should not be construed as necessarilyextending in a constant configuration around the entire periphery of thelens.

Although the anterior peripheral land or region 46 is shown as beinglinear and substantially perpendicular to the optical axis OA, otherconfigurations are contemplated. For example, the peripheral land 46could be other than linear, i.e., convex or concave with respect to aplane through the medial plane of the optic. Or, the peripheral land 46could be angled toward or away from the anterior side. Further, theremay be more than one surface defining the peripheral land 46, such as acurved and a linear surface.

FIGS. 4 and 5 illustrate two further optics 60 a and 60 b that havesubstantially the same configuration as the optic 40 of FIG. 3. That is,both optics 60 a and 60 b have an optical axis OA, a convex anteriorface AF, a convex posterior face PF, and a peripheral edge 62 a, 62 b,respectively. Each peripheral edge 62 a, 62 b, comprises, respectively,a rounded transition surface 64 a, 64 b, and anterior peripheral land 66a, 66 b that is substantially perpendicular to the optical axis OA, aposterior edge corner 70 a, 70 b, an edge surface 72 a, 72 b that issubstantially parallel to the optical axis OA, and an anteriorly-facingedge surface 74 a, 74 b that is non-parallel to the optical axis OA.

FIGS. 3, 4 and 5 illustrate optics of similar configuration that havedifferent dimensions based on their different magnitude of opticalcorrection, or diopter value. The optic 40 of FIG. 3 has an intermediatecorrection diopter value of 20, the optic 60 a of FIG. 4 has a dioptervalue of 10, and the optic 60 b of FIG. 5 has a diopter value of 30.These relative diopter values are reflected in the relative convexity ofeach. That is, the smallest diopter value optic 40 shown in FIG. 4 hasrelatively shallow convex anterior face AF and posterior face PF. Incontrast, the larger diopter value optic 60 b in FIG. 5 has a largerconvexity for both the anterior face AF and posterior face PF.

Various dimensions for the respective peripheral edges of the exemplaryoptics shown in FIGS. 3-5 are also given in FIGS. 4 and 5. That is, thethickness of each peripheral edge is given as t, the thickness of theparallel edge surface is given as A, the angle of the non-parallel edgesurface is given as θ, and a radius of curvature of the transitionsurface is given as R.

The following tables provide exemplary values for these dimensions forthe optics 60 a and 60 b of FIGS. 4 and 5. These dimensions areconsidered suitable for optics 60 a and 60 b that are made fromsilicone. It should be noted that the dimensions for the optic 40 ofFIG. 3 are desirably approximately equal to those for the optic 60 b ofFIG. 5. It should also be noted that the following dimensions arebelieved to provide certain benefits as far as reducing glare and PCO inIOLs, although not all the dimensions have been selected for either ofthose particular purposes. For example, some of the dimensions may bedesirable to facilitate manufacturing of the respective IOL.

Table I provides exemplary values for optics that are made from acrylic.

TABLE I EXEMPLARY DIMENSIONS FOR SILICONE IOLs T₁ (in) t₂ (in) A₁ (in)A₂ (in) θ₁ θ₂ R₁ (in) R₂ (in) .023- .012- .002- .002- 13-17° 13-17°.001- .004- .027 .014 .007 .007 .003 .006

Table II provides exemplary values for the same dimensions as shown inFIGS. 4-5, but for optics that are made from acrylic. In this case, thesubscript “1” pertains to optics having a diopter value of 10, while thesubscript “2” pertains to optics having a diopter value of either 20 or30.

TABLE II EXEMPLARY DIMENSIONS FOR ACRYLIC IOLs t₁ (in) t₂ (in) A₁ (in)A₂ (in) θ₁ θ₂ R₁ (in) R₂ (in) .015- .013- .002- .002- 13-17° 13-17°.004- .004- .019 .017 .007 .007 .008 .008

As is apparent from FIGS. 3-5, the convexity of the various lenses alongthe optical axis OA increases with increasing diopter value (theposterior face and especially the anterior face are more highly convex).However, some surgeons prefer the intraocular lenses to haveapproximately the same volume or center thickness at the optical axisregardless of diopter power. This permits the surgeon to use the samesurgical technique across the diopter range. Therefore, the presentinvention contemplates varying the overall diameter of the optic fordifferent diopter values. That is, the center thickness of theintraocular lenses for different diopter values remains the sameregardless of diameter. Therefore, the diameter of lenses having greaterconvexity should be reduced to reduce the center thickness, and thediameter of flatter lenses should be increased, both to an intermediatevalue. For example, the diameter of the lower diopter value optic 60 ashown in FIG. 4 may be increased so that the center thickness is closerto the intermediate diopter value optic 40 shown in FIG. 3. Likewise,the diameter of the higher diopter value optic 60 b shown in FIG. 5 maybe decreased so that the center thickness is closer to the optic 40shown in FIG. 3.

Therefore, the present invention contemplates a set of intraocularlenses having varying diopter values wherein the diameter of the opticsvaries generally inversely (although not necessarily linearly) withrespect to the diopter value. In this way, a set of intraocular lenseshaving approximately the same center thickness can be provided to thesurgeon to help make the implantation procedure more consistent andpredictable. One example of a set of intraocular lenses may include theoptics shown in FIGS. 3-5. The lower diopter lens 60 a of FIG. 4 mayhave a diameter of approximately 6.25 mm, the intermediate diopter lens40 of FIG. 3 may have a diameter of 6.0 mm, and the higher diopter lens60 b of FIG. 5 may have a diameter of 5.75 mm. Advantageously, anincreased diameter for lower diopter lenses corresponds to humanphysiology. That is, people who require lower diopter lenses typicallyhave larger eyes, while people requiring high diopters tend to havesmaller eyes.

FIG. 6 illustrates a section of the peripheral edge 42 of the optic 40of FIG. 3 with a plurality of discrete light rays 80 a, 80 b, 80 c,entering the peripheral edge from the anterior side. Therefracted/reflected path of each light ray through the peripheral edge42 is indicated, with the path of each light ray as it exits theperipheral edge 42 indicated as 82 a, 82 b and 82 c.

FIG. 6 thus illustrates the advantageous characteristic of theperipheral edge 42 in diffusing incoming parallel light rays so that thereflected light intensity is reduced. That is, any light that ordinarilywould reflect back towards the optical axis at near its originalintensity is instead diffused to reduce glare in the IOL. The presentinvention contemplates utilizing a curved or rounded transition surface,such as the surface 44, in combination with one or more planar edgesurfaces that are not parallel to the optical axis, such as the edgesurface 54. In the illustrated embodiment, the peripheral edge 42further includes the edge surface 52 that is substantially parallel tothe optical axis. It is believed that the combination of the roundedtransition surface 44 on the anterior side leading to theanteriorly-facing edge surface 54 substantially reduces glare within theoptic 40.

FIGS. 7-9 each illustrates one half of an optic of an IOL in sectionhaving a configuration that reduces glare. In one design, incoming lightis refracted so as to decrease the probability of light reflecting offthe peripheral edge surfaces toward the optical axis relative toconventional lenses. In another design, incoming light reflects off ofan internal peripheral edge surface at a shallow angle of incidence nottoward the optical axis so as to decrease the probability of lightreflecting off of other edge surfaces relative to conventional lenses.All of the optics disclosed in FIGS. 7-9 comprise an optical axis OA, aconvex anterior face AF, and a convex posterior face PF.

An optic 90 seen in FIG. 7 includes a peripheral edge 92 having a firstedge surface 94 that is linear and substantially parallel to the opticalaxis OA, and an anteriorly-facing second edge surface 96 that is linearand non-parallel to the optical axis. With respect to the partialcross-section of the optic 90 seen in FIG. 7, the anteriorly-facingsecond edge surface 96 is angled in the counter-clockwise (ccw)direction with respect to the optical axis OA. The edge surfaces 94 and96 meet in the mid-portion of the peripheral edge 92 at a discontinuity98. A posterior edge corner 100 separates the peripheral edge 92 fromposterior face PF, while an anterior edge corner 102 separates theperipheral edge from a peripheral land 104 that is substantiallyperpendicular to the optical axis.

An incoming light ray 106 is illustrated passing through the peripheralland 104 to reflect off the second edge surface 96 within the optic 90.The resulting reflected ray 108 is deflected through the optic 90 sothat it misses the first edge surface 94. In this manner, a substantialportion of the light entering the optic 90 in the region of theperipheral edge 92 is reflected at a relatively shallow angle ofincidence off of the second edge surface 96, and is not reflected offthe first edge surface 94 toward the optical axis OA. Thus, glare isreduced. To achieve this result, the anteriorly-facing second edgesurface 96 is desirably angled at least about 10° with respect to theoptical axis OA.

FIG. 8 illustrates an optic 110 having a peripheral edge 112 comprisinga single anteriorly-facing edge surface 114 that is linear andnon-parallel with respect to the optical axis OA. Thus, the optic 110has a single conical anteriorly-facing edge surface 114. A posterioredge corner 116 separates the edge surface 114 from the posterior facePF, and an anterior edge corner 118 separates the edge surface 114 froma peripheral land 120 that is substantially perpendicular to the opticalaxis OA. An incoming light ray 122 is illustrated striking theperipheral land 120 and passing through the optic 110. Because of theanteriorly-facing angle of the edge surface 114, the light ray mayrefract slightly on passage through the optic 110, as indicated at 124,but will not reflect off the surface edge 114. That is, the posterioredge corner 116 is located farther radially outward from the opticalaxis OA than the anterior edge corner 118 and a substantial portion oflight passing into the region of the peripheral edge 112 simply passesthrough the material of the optic 110. To achieve this result, theanteriorly-facing edge surface 114 is desirably angled at least about 5°with respect to the optical axis OA.

FIG. 9 illustrates an optic 130 that is substantially similar to theoptic 110 of FIG. 8, with a peripheral edge 132 defined by a singleanteriorly-facing edge surface 134 that is linear and non-parallel withrespect to the optical axis OA. Thus, the optic 130 has a single conicalanteriorly-facing edge surface 134. Again, a posterior edge corner 136separates the peripheral edge 132 from the posterior face PF. Ananterior edge corner 138 separates the peripheral edge 132 from theanterior face AF, and there is no anterior peripheral land. The path ofa light ray 140 passing through the region of the peripheral edge 132illustrates the elimination of any reflection off a peripheral edgesurface. That is, a substantial portion of light striking the optic 130from the anterior side simply passes through the optic withoutreflecting toward the optical axis OA. To achieve this result, theanteriorly-facing edge surface 134 is desirably angled at least about 5°with respect to the optical axis OA.

FIGS. 10-13 illustrate a number of optics of the present invention thatare configured to transmit internal light radially outward from theirperipheral edges as opposed to reflecting it toward the optical axis.This can be done in a number of ways, all of which result in lighthitting the peripheral edge from the interior of the optic at an anglethat is less than the critical angle for the refractive index of thelens material. Again, each of the optics in FIGS. 10-13 includes anoptical axis OA, a convex anterior face AF, and a convex posterior facePF.

FIGS. 10 and 11 illustrate two substantially similar optics 150 a, 150 bthat will be given corresponding element numbers. Each of the optics 150a, 150 b has a peripheral edge 152 b, 152 b defined by an edge surface154 a, 154 b that is linear and substantially parallel to the opticalaxis OA. A posterior edge corner 156 a, 156 b separates the edge surface154 a, 154 b from the respective posterior face PF. Both optics 150 a,150 b include an acute anterior edge corner 158 a, 158 b separating theedge surface 154 a, 154 b from an anterior peripheral land 160 a, 160 b.The peripheral lands 160 a, 160 b are shown as linear andnon-perpendicular with respect to the optical axis OA, but it should beunderstood that non-linear lands may perform equally as well, and mayfurther diffuse the incoming light. The peripheral land 160 a of theoptic 150 a of FIG. 10 joins with its anterior face AF at adiscontinuity 162. On the other hand, a peripheral land 164 that islinear and substantially perpendicular to the optical axis OA joins theperipheral land 160 b of the optic 150 b of FIG. 11 to its anterior faceAF; that is, there are two peripheral lands 160 b and 164 on the optic150 b of FIG. 11.

Incoming light rays 166 a, 166 b are illustrated in FIGS. 10 and 11striking the respective peripheral lands 160 a, 160 b and passingthrough the material of the respective optics 150 a, 150 b toward theedge surfaces 154 a, 154 b. Because of the particular angle of theperipheral lands 160 a, 160 b, the light rays strike the edge surfaces154 a, 154 b at angles that are less than the critical angle for therefractive index of the lens material. Therefore, instead of reflectingoff of the edge surfaces 154 a, 154 b, the light rays pass through theperipheral edges 152 a, 152 b as indicated by the exit rays 168 a, 168b. The included angles between the edge surfaces 154 a, 154 b and theperipheral lands 160 a, 160 b are shown α₁ and α₂. These angles arepreferably less than 90°, more preferably within the range of about 45°to 88°, and most preferably within the range of about 70° to 88°. Ofcourse, these ranges may differ depending on the refractive index of thematerial.

FIGS. 12 and 13 illustrate similar optics 170 a, 170 b that each have aperipheral edge 172 a, 172 b defined by a posteriorly-facing edgesurface 174 a, 174 b that is linear and non-parallel with respect to theoptical axis OA. A posterior edge corner 176 a, 176 b separates the edgesurface 174 a, 174 b from the posterior face PF. On the optic 170 a ofFIG. 12, an anterior edge corner 178 a separates the edge surface 174 afrom the anterior face AF, without a peripheral land. In contrast, asseen in FIG. 13 an anterior edge corner 178 b separates the edge surface174 b from a peripheral land 180 that is linear and substantiallyperpendicular to the optical axis OA of the optic 170 b. The peripheralland 180 meets the anterior face AF at a discontinuity 182.

The angles of the anterior edge corners 178 a and 178 b are indicated atβ₁ and β₂. The magnitude of the angle β₁ depends both on the convexityof the anterior face AF and the angle of the posteriorly-facing edgesurface 174 a with respect to the optical axis OA. The anterior face AFmay have widely differing convexities, but desirably theposteriorly-facing edge surface 174 a is at least 2° (clockwise in thedrawing) with respect to the optical axis OA. Therefore, the angle β₁ ispreferably less than about 120°, and more preferably are within therange of about 70° to 120°. The magnitude of the angle β₂ seen in FIG.13 depends both on the angle of the peripheral land 180 and the angle ofthe posteriorly-facing edge surface 174 b with respect to the opticalaxis OA. The peripheral land 180 is shown as linear and perpendicularwith respect to the optical axis OA, but it should be understood thatnon-linear and non-parallel lands may perform equally as well. Desirablythe posteriorly-facing edge surface 174 b is at least 2° (clockwise inthe drawing) with respect to the optical axis OA. Therefore, the angleβ₂ is preferably acute, and more preferably is within the range of about30° to 88°. Of course, these ranges may differ depending on therefractive index of the material.

FIGS. 12 and 13 illustrate incoming light rays 184 a, 184 b that strikethe anterior side of the respective optic 170 a, 170 b adjacent theperipheral edges 172 a, 172 b and subsequently pass through the materialof the optic and through the edge surfaces 174 a, 174 b withoutreflection. Again, this phenomenon is caused by the angles at which thelight rays strike the edge surfaces 174 a, 174 b, which are lower thanthe critical angle for the refractive index of the lens material. As aresult, the light rays simply pass through the peripheral edges 172 a,172 b without reflecting back towards the optical axis OA.

FIG. 14 a illustrates a further embodiment of an IOL 200 of the presentinvention having an optic 202 and a plurality of fixation members 204extending radially outward therefrom, only one of which is shown. FIG.14 b is an enlargement of a peripheral edge region of the optic 202. Asalways, the optic 202 includes an optical axis OA, a convex anteriorface AF, and a convex posterior face PF.

With reference to FIG. 14 b, the optic 202 includes a peripheral edge206 defined by an anteriorly-facing edge surface 208 that is linear andnon-parallel with respect to the optical axis OA. A curved or roundedtransition surface 210 smoothly blends the linear edge surface 208 tothe convex anterior face AF. An acute posterior edge corner 212separates the edge surface 208 from a peripheral land 214 that is linearand substantially perpendicular to the optical axis OA. The peripheralland 214 joins with the convex posterior face PF at a discontinuity 216.FIG. 14 a illustrates a plane 218 coincident with the circular posterioredge corner 212. This plane represents a separation line between twomold halves used to form the optic 202. In this manner, the acuteperipheral edge corner 212 can be easily formed between the mold halves.

The embodiment shown in FIGS. 14 a and 14 b incorporates a combinationof several advantageous features previously described. That is, therounded transition surface 210 tends to diffuse light rays entering fromthe anterior side, as described above with respect to the embodiment ofFIGS. 3-5. In addition, the edge surface 208 is angled in such a mannerthat some of the light passing through the transition surface 210 willnot even strike it, and the light that does will be reflected at arelatively shallow angle of incidence that reduces glare.

FIGS. 15-17 illustrate the peripheral edges of three optics 220 a, 220b, 220 c having similar shapes. The optic 220 a of FIG. 15 has aperipheral edge defined by an anteriorly-facing surface 222 a that islinear and non-parallel with respect to the optical axis, an acuteposterior edge corner 224 a, and a rounded anterior transition surface226 a blending with the anterior face AF. A peripheral land 228 a thatis generally perpendicular with respect to the optical axis extendsbetween the posterior face PF and the edge corner 224 a, and joins withthe posterior face PF at a discontinuity 230 a. The included anglebetween the surface 222 a and the peripheral land 228 a is relativelysmall, and the rounded transition surface 226 a protrudes slightlyoutward from the surface 222 a.

The peripheral edge of the optic 220 b shown in FIG. 16 also includes ananteriorly-facing surface 222 b that is linear and non-parallel withrespect to the optical axis, an acute posterior edge corner 224 b, and arounded anterior transition surface 226 b blending with the anteriorface AF. A peripheral land 228 b that is not perpendicular to theoptical axis extends between the posterior face PF and the edge corner224 b. The peripheral land 228 b joins with the posterior face PF at adiscontinuity 230 b. The included angle between the surface 222 b andthe peripheral land 228 b is slightly larger than that shown in FIG. 15,primarily because the surface 222 b has a shallower angle with respectto the optical axis than the surface 222 a.

The peripheral edge of the optic 220 c shown in FIG. 17 also includes ananteriorly-facing surface 222 c that is linear and non-parallel withrespect to the optical axis, an acute posterior edge corner 224 c, and arounded anterior transition surface 226 c blending with the anteriorface AF. A peripheral land 228 c that is not perpendicular to theoptical axis extends between the posterior face PF and the edge corner224 c. The peripheral land 228 c joins with the posterior face PF at adiscontinuity 230 c. The optic 220 c is fairly similar to the optic 220b, but has a slightly less convex posterior face PF.

FIG. 18 illustrates the peripheral edge of an optic 240 having asaw-tooth or baffled edge surface 242. The edge surface 242 is generallyaligned to face the anterior side of the optic 240 and includes multipletooth facets or surfaces 244 a and 244 b defining peaks 246 and troughs248. Each tooth surface 244 a is desirably parallel to the othersurfaces on the same side of each tooth, as is each tooth surface 244 bwith respect to the others on the other side of each tooth. Theperipheral edge of the optic 240 further includes a posterior edgecorner 250 and a rounded transition surface 252 blending into theanterior face AF. A peripheral land 254 that is generally perpendicularto the optical axis extends between the posterior face PF and the edgecorner 250.

Still with reference to FIG. 18, light striking the peripheral edge ofthe optic 240 from the anterior side is scattered and diffused uponpassage through the baffled edge surface 242 and the rounded transitionsurface 252. This helps reduce glare within the optic 240. In addition,the edge surface 242 is angled so as to be non-parallel with respect tothe optical axis, and thus some of the light rays internal to the optic240 will not even strike this edge surface to further reduce glare.

An optic 260 that includes a linear posteriorly-facing edge surface 262is seen in FIG. 19. The peripheral edge of the optic 260 comprises theedge surface 262, a rounded transition surface 264 blending to theanterior face AF, and a peripheral edge corner 266 adjacent a shortperipheral land 268. The advantages of the posteriorly-facing edgesurface 262 were described previously with respect to FIGS. 12 and 13,and primarily involved light being transmitted through the edge surfaceas opposed to being internally reflected off of it. Of course, lightthat is transmitted through the edge surface 262 as opposed to beingreflected off of it cannot contribute to glare. In addition, the roundedtransition surface 264 helps to diffuse light rays striking theperipheral edge, thus further reducing glare.

FIG. 20 illustrates an optic 280 having both an anterior edge corner 282and posterior edge corner 284. A posteriorly-facing edge surface 286extends from the anterior edge corner 282 to an apex 288, and ananteriorly-facing edge surface 290 extends between the apex and theposterior edge corner 284. The apex 288 defines the midpoint of agroove, and the resulting configuration in cross-section is somethinglike a forked-tongue. A pair of peripheral lands 292 a, 292 b extendsbetween the edge corners 282, 284 and the respective anterior andposterior faces of the optic 280. The peripheral lands 292 a, 292 b aredesirably perpendicular to the optical axis. Again, the provision oflinear edge surfaces that are non-parallel with respect to the opticalaxis helps reduce glare within the optic 280. Furthermore, therelatively sharp edge corners 282, 284 helps reduce PCO by inhibitingcell growth on both the anterior and posterior sides of the optic 280.

Another embodiment of the invention seen in FIG. 21 has an optic 300with an anterior face 302, a posterior face 304, an anterior peripheralregion 306, a posterior peripheral region 308 and a peripheral edgesurface 310. The peripheral edge surface 310 has a continuously curved,concave configuration, for example, in cross-section. The peripheraledge surface 310 intersects anterior peripheral region 306 at anteriorperipheral corner edge 312 at an angle of about 70°. Corner edge 312 isat a discontinuity between anterior face 302 (anterior peripheral region306) and peripheral edge surface 310, and circumscribes optical axis314. Peripheral edge surface 310 intersects posterior peripheral region308 at posterior peripheral corner edge 316 at an angle of about 70°Corner edge 316 is at a discontinuity between posterior face 304(posterior peripheral region 308) and peripheral edge surface 310, andcircumscribes optical axis 314.

The anterior and posterior peripheral regions 306 and 308 extendradially inwardly, for example, for a distance of about 0.1 mm to about1.0 mm or more (about 0.5 mm as shown in FIG. 21), from the peripheraledge surface 310, and peripheral corner edge 312 and 316 respectively,and are substantially planar, more particularly, substantiallyperpendicular to the optical axis 314 of optic 300. Anterior face 302includes an additional anterior region 318 which is convex, not planar.Posterior face 304 includes an additional posterior region 320 whichalso is convex, not planar. The dimension of optic 300 between anteriorface 302 and posterior face 304 at the peripheral regions 306 and 308 issmaller than the same dimension at the optical axis 314.

It is found that implanting an IOL having the optic 300 in the capsularbag of an eye effectively inhibits or retards cell migration or growth,for example, epithelial cell migration or growth, from the eye ontoand/or over the anterior and posterior faces 302 and 304 of optic 300.In addition, it is found that a reduced amount of edge glare is obtainedwith an IOL having the optic 300 implanted in the capsular bag of theeye.

Without wishing to limit the invention to any particular theory ofoperation, it is believed that an IOL having the optic 300 provides forinhibition of cell migration or growth onto and/or over the optic 300because of the sharp or abrupt peripheral corner edges 312 and 316.Thus, it is believed that the cells from the eye have a reduced tendencyto grow onto and/or over the anterior face 302 and posterior face 304relative to a substantially identical IOL without such peripheral corneredge. In addition, it is believed that the reduced glare obtained usingan IOL having the optic 300 results from the curved configuration of theperipheral edge surface 310. Thus, an IOL having the optic 300 includingthe substantially continuously curved peripheral edge surface 310provides reduced glare relative to a substantially similar IOL having aperipheral edge surface which is substantially parallel, for example, incross-section, to the optical axis of the IOL.

FIG. 22 illustrates an alternate embodiment of an IOL in accordance withthe present invention. This IOL has an optic shown generally at 330.Except as expressly described herein, optic 330 is structured andfunctions similarly to optic 300.

The principal difference between the optic 330 and the optic 300 relatesto the shape of the anterior face 332 and the shape of posterior face334. Specifically, anterior face 332 is convex throughout, and optic 330does not include a substantially planar anterior peripheral region. Thisconvex anterior face 332 intersects peripheral edge surface 336 at sharpanterior peripheral corner edge 338. Similarly, posterior face 334 isconvex throughout, and optic 330 does not include a substantially planarposterior peripheral region. This convex posterior face 334 intersectsperipheral edge surface 336 at sharp posterior peripheral corner edge340. The specific configuration of anterior face 332 and posterior face334 can be independently provided to address the needs of any givenspecific application including the following factors; the visioncorrection or corrections desired, the size of optic 330, the size ofthe eye in which an IOL having optic 330 is to be placed and the likefactors. Optic 330 inhibits or retards cell migration or growth andprovides a reduced amount of edge glare as does the optic 300, describedabove.

FIG. 23 illustrates a further embodiment of an IOL in accordance withthe present invention. This IOL has an optic shown generally at 350.Except as expressly described herein, optic 350 is structured andfunctions similarly to optic 330.

The principal difference between optic 350 and optic 330 relates to theshape of peripheral edge surface 352. Specifically, the curvature ofperipheral edge surface 352 is more complex relative to the curvature ofperipheral edge surface 336. In particular, the curvature of edgesurface 352 varies substantially continuously while the curvature ofedge surface 336 is a substantially constant concave arc (incross-section). Peripheral edge surface 352 is configured to reduce theamount of edge glare obtained with optic 350 in the eye relative to, forexample, IOL 30 of FIG. 2. The specific configuration or curvature ofperipheral edge surface 352 is provided to address the needs of aspecific application, including the following factors: the size of theoptic 350, the size of the eye in which an IOL having the optic 330 isto be placed and the like factors.

FIG. 24 illustrates an additional embodiment of the present invention.The IOL illustrated in FIG. 24 has an optic shown generally at 360.Except as expressly described herein, optic 360 is structured andfunctions similarly to optic 330.

The primary difference between optic 360 and optic 330 relates to theconfiguration of peripheral edge surface 362. Specifically, thecurvature of peripheral edge surface 362 varies substantiallycontinuously (in a manner which is substantially the reverse of thecurvature of peripheral edge surface 352 of optic 350) while thecurvature of edge 336 is a substantially constant concave arc (incross-section). The peripheral edge surface 362 of optic 360 iseffective in reducing the glare caused by the presence of optic 360 inthe eye relative to the glare obtained with IOL 30 of FIG. 2 in the eye.

FIG. 25 illustrates an additional embodiment of an IOL in accordancewith the present invention. Except as expressly described herein, thisIOL, having an optic shown generally at 370 is structured and functionssimilarly to optic 330.

The primary difference between optic 370 and optic 330 relates to theconfiguration of the peripheral edge surface 372. Specifically,peripheral edge surface 372 includes a first portion 374 which isconcave relative to the optical axis 376 of optic 370. Peripheral edgesurface 372 also includes a second portion 378 which is convex relativeto the optical axis 376 of optic 370. Thus, the curvature of theperipheral edge surface of the present IOLs, for example, peripheraledge surface 372 of optic 370, can be relatively complex. Peripheraledge surface 372 is effective to provide reduced glare in the eyerelative to IOL 30 of FIG. 2. In addition, it should be noted that theperipheral edge surface 372 intersects anterior face 380 at anteriorperipheral corner edge 382 at an angle of about 90°. Similarly, theperipheral edge surface 372 intersects posterior peripheral region 384at posterior peripheral corner edge 386 at an angle of about 90°.

Optic 370, as with all of the IOLs in accordance with the presentinvention, is effective in inhibiting or retarding cell migration orgrowth from the eye onto or over the optic 370.

FIG. 26 illustrates a further alternate embodiment of an IOL inaccordance with the present invention. This IOL has an optic showngenerally at 400. Except as expressly described herein, optic 400 isstructured and functions substantially similarly to optic 330.

The primary differences between optic 400 and optic 330 relate to theconfiguration of peripheral edge surface 402 and the configuration ofthe intersection between anterior face 404 and peripheral edge surface402 of optic 400. Specifically, peripheral edge surface 402 has acontinuously curved configuration somewhat similar to peripheral edgesurface 372 of optic 370. Also, the anterior face 404 intersectsperipheral edge surface 402 on a curve (that is on a continuity not at adiscontinuity). In other words, the intersection of anterior face 404and peripheral edge surface 402 is smooth or continuous, not sharp ordiscontinuous.

Optic 400 is effective in reducing the amount of glare obtained withoptic 400 in the eye relative to IOL 30 of FIG. 2 in the eye. Also,optic 370 is effective in retarding or inhibiting migration from the eyeonto and/or over cell growth or migration from the eye onto and/or overthe posterior face 406 of optic 400.

FIG. 27 illustrates a still further embodiment of an IOL in accordancewith the present invention. Except as expressly described herein, thisIOL, having an optic shown generally at 410 is structured and functionssimilarly to optic 330.

The primary difference between optic 410 and optic 330 relates to theconfiguration of the peripheral edge surface 412 and to theconfiguration of posterior face 414. Specifically, peripheral edgesurface 412 is convex relative to the optical axis 416 of optic 410.Peripheral edge surface 412 does not intersect anterior face 418 at asharp or discontinuous corner edge, but does intersect posterior face414 at an obtuse angle at posterior peripheral corner 420. Posteriorface 414 includes a peripheral region 422 which is substantiallyperpendicular to optical axis 416. Anterior face 418 includes aperipheral region 424 which is roughened to be at least partially opaqueto the transmission of light. The combination of the convex peripheraledge surface 412 and the at least partially opaque peripheral region 424is particularly effective in reducing glare, for example, from corner420, obtained with an IOL having optic 410 in the eye.

FIG. 28 illustrates still another embodiment of an IOL in accordancewith the present invention. This IOL has an optic shown generally at440. Except as expressly described herein, optic 440 is structured andfunctions substantially similarly to optic 330.

The primary differences between optic 440 and optic 330 relate to theconfiguration of peripheral edge surface 442, the configuration of theintersection between anterior face 444 and peripheral edge surface 442of optic 440 and the configuration of posterior face 446. Peripheraledge surface 442 includes a first portion 448 which is convex relativeto optic axis 450 of optic 440. Peripheral edge surface 442 alsoincludes a second portion 452 which transitions from first portion 448and intersects posterior face 446 at corner 454. Peripheral edge surface442 does not intersect anterior face 444 at a sharp or discontinuancecorner edge. Posterior face 446 includes a peripheral region 456 whichis substantially perpendicular to optical axis 450. Anterior face 444includes the peripheral region 458 which is roughened to be at leastpartially opaque to the transmission of light. Region 460 of peripheraledge surface 442 and region 462 of posterior face 446 are also roughenedto be at least partially opaque to the transmission of light. Thecombination of the peripheral edge surface 442 and the at leastpartially opaque regions 458, 460, 462 is particularly effective inreducing glare, for example, from corner edge 454, obtained with optic440 in the eye.

In addition to designing the geometry of the peripheral edge of theintraocular lenses of the present invention to reduce glare andposterior capsule opacification (PCO), the edges and surfaces near theedges may be “textured” or frosted to cause scatter of light impingingon the peripheral region. Such scattering helps reduce edge glare. Inaddition, use of texture in combination with various edge geometries mayhelp reduce PCO. Various texturing regimens may be used, as described inU.S. Pat. No. 5,693,094, entitled IOL for Reducing SecondaryOpacification, hereby expressly incorporated by reference. With respectto specific embodiments, IOLs made of silicone desirably includetexturing/frosting on at least one edge surface as well as on aperipheral region of the posterior face, or intermediate land. AcrylicIOLs, on the other hand, desirably include texturing/frosting on atleast one edge surface, and preferably on an edge surface that isparallel to the optical axis.

The intraocular lenses of the present invention may be manufacturedusing a variety of techniques, including injection molding, compressionmolding, lathing, and milling. Those of skill in the art will understandhow to form the mold dies, or program the cutting tools to shape thelenses in accordance with present invention. Importantly, care must betaken to avoid rounding the various corners or discontinuities for theparticular optic during the polishing process. Therefore, the cornersmust be masked or otherwise protected while the lens is being polished.Alternatively, the unmasked lens may be polished and then the variousedge surfaces re-cut to insure sharp corners.

With reference back to FIG. 1, the design of the fixation members 24 a,24 b may play an important role in reducing the risk of PCO for anyparticular lens. That is, the fixation members 24 a, 24 b must bedesigned such that during capsular contraction, there is enough axialmovement and accompanying bias of the lens against the posterior capsuleto seal the capsule around the posterior edge corners of the lens. Avariety of fixation members 24 a, 24 b are known in the art that canprovide the required posterior bias to the lens. The preciseconfiguration of the fixation members 24 a, 24 b may vary depending onthe overall lens diameter, the diameter of the optic, the angle of thefixation member, the stiffness of the fixation member material, thegauge of the fixation member, the geometry of the fixation member, andthe way in which the fixation member is attached to the lens.

The present invention very effectively provides IOLs which inhibit cellgrowth or migration, in particular epithelial cell growth or migrationfrom a capsular bag, onto and/or over the IOL optics. In addition, theIOLs produce reduced glare, in particular edge glare, relative to a lenshaving a peripheral edge which is substantially parallel, incross-section, to the optical axis of the IOL optic. These benefits areachieved with IOLs which are easily manufactured and inserted in theeye. Such IOLs can be made of any suitable material, and provideeffective performance and substantial benefits to the patient.

Although the use of a roughened or otherwise irregular surface on aportion of an intraocular lens has been proposed (e.g., see U.S. Pat.No. 5,549,670 to Young, et al.), the purpose has primarily been toprovide a barrier to cell migration across the lens. The presentinvention contemplates the use of specific roughened or otherwisepartially opaque surfaces around the peripheral edge area of theintraocular lens to greatly reduce glare from incoming light. Asexplained above, the peripheral edge and the adjacent surfaces on theanterior and/or posterior face of the optic of the interocular lens aredesirably at least partially opaque to produce the beneficial glarereduction. Preferably, all three of these external surfaces—i.e., theperipheral edge, the anterior peripheral region, and posteriorperipheral region—are partially opaque to the transmission of light suchthat internally and inwardly reflecting rays from incoming light aresubstantially eliminated. That is, light rays striking the peripheraledge or adjacent regions are absorbed to such an extent on passagethrough and between the partially opaque surfaces that they do notreflect inward through the optic and thus do not cause unwanted visualsymptoms (e.g., so-called “pattern glare”). Most preferably, all but thecentered light-transmitting or refractive portion of the optic isrendered partially opaque to the transmission of light so as to maximizeglare reduction. In practice, light scatters more than once if multiplesurfaces are rendered partially opaque or roughened. Incoming lightscatters ones through the anterior surface and hits the peripheral edgeand scatters again. If roughening is provided on the posterior surface,the already scattered light scatters again and thus the intensity of anyreflected glare is extremely low.

In addition to providing a particular external surface characteristic,such as roughening, to increase the light-absorbing quality of thenon-refractive portion of the intraocular lens, a material having alight absorbing color or composition may be used. The color can be mixedinto the otherwise optically transparent lens material (e.g., silicone)and molded around the peripheral edge area. Alternatively, the centraloptic portion can be insert molded around a colored ring. If theintraocular lens is machined, the starting blank can be formed with aring of color and the optic or refractive surfaces can then be machined,typically with a lathe, in the central region. Small particles orbubbles within the lens material may also produce the same result. Thelight absorbing color or composition may be provided externally, such asjust on the peripheral edge surface, or on one of the anterior orposterior peripheral regions, or may be provided throughout the internalstructural matrix of the peripheral edge.

In a most preferred embodiment, the partially opaque surfaces or lightabsorbing internal or external structures are utilized in combinationwith specific edge configurations, such as those described above. Forexample, a rounded anterior corner of the peripheral edge has been foundto reduce unwanted light ray reflection and glare. Likewise, providingtwo differently-angled linear (in radial cross-section) peripheral edgesurfaces in conjunction with the rounded anterior edge corner furtherreduces glare.

Tests and simulations indicate that glare reduction of lenses producedin accordance with the present invention surpasses that of other lensdesigns. FIGS. 29 a, 29 b and 30 illustrate results of computersimulations or models of light passing through a number of intraocularlenses in an environment that mimics the eye. FIGS. 29 a and 29 b aremodels of intraocular lenses of the present invention, while FIG. 30 isa model of an intraocular lens of the prior art.

With reference to FIG. 29 a, an intraocular lens 500 a is shown centeredalong an optical axis OA and spaced in the posterior direction from aconvex corneal surface 502 a. A retinal target is also shown centeredalong the optical axis OA posteriorly from the intraocular lens 500 a.An angular incoming light beam 506 a, schematically composed of aplurality of individual light rays, is shown refracting and reflectingoff both the corneal surface 502 a and the intraocular lens 500 a.Specifically, a plurality of rays 508 a reflect off the corneal surface,while a further plurality of rays 510 a reflect off the intraocularlens. A large majority of the light is refracted correctly, as seen bylight rays 512 a, reaching the target retinal surface 504 a, while onlya small portion of the light 514 a is refracted incorrectly to theretinal surface 504 a. Although this so-called “pattern glare” exists,it is very low and the local contrast is very close to zero.

Similarly, in FIG. 29 b an intraocular lens 500 b is shown centeredalong an optical axis OA and spaced in the posterior direction from aconvex corneal surface 502 b. A retinal target is also shown centeredalong the optical axis OA posteriorly from the intraocular lens 500 b.An angular incoming light beam 506 b, schematically composed of aplurality of individual light rays, is shown refracting and reflectingoff both the corneal surface 502 b and the intraocular lens 500 b. Aswith FIG. 29 a,a plurality of rays 508 b reflect off the cornealsurface, while a further plurality of rays 510 b reflect off theintraocular lens 500 b. A large majority of the light is refractedcorrectly, as seen by light rays 512 b, reaching the target retinalsurface 504 b, while only a small portion of the light 514 b isrefracted incorrectly to the retinal surface 504 b. Again, the patternglare is very low and the local contrast is very close to zero.

The intraocular lenses 500 a and 500 b are both molded silicone lenseshaving a central, circular optic portion that has a peripheral edge withanterior and posterior square corners. The optic portion of both lenses500 a and 500 b is roughened or frosted over its entire exterior surfaceexcept in the central optically refractive region. These lenses are bothbiconvex in the central optically refractive region. The peripheral edgeof each of the lenses is a cylindrical surface centered on the opticalaxis. The diameter of the optic portion of the lens 500 a is 6.00 mm,while the diameter of the optic portion of the lens 500 b is 5.50 mm.

FIG. 30 illustrates a ray tracing model of an intraocular lens 600 notmade in accordance with the present invention; specifically, the lensmodel is denoted 60ACSC and manufactured by Alcon. The lens has an opticportion which is similarly configured to the optic portions of thelenses 500 a and 500 b, but is only roughened on the outer or peripheraledge surface.

FIG. 30 illustrates an optical system comprising the intraocular lens600, a convex corneal surface 602, and the target retinal surface 604.An incoming light beam 606 schematically shown as a plurality ofindividual light rays first reflects at 608 off the corneal surface 602.A majority of the light beam 606 refracts through the intraocular lens600 shown at 612, but there is some pattern glare as seen at 614 thatstrikes the retinal surface 604. The magnitude of the glare for the lens600 is an order of intensity higher than the glare in the intraocularlens models of FIGS. 29 a and 29 b, and the glare local contrast is alsomuch higher.

In addition to the location of roughening, an important considerationwhen manufacturing intraocular lenses in accordance with the presentinvention is the magnitude of roughness or frosting. The magnitude ofroughness can be defined in a number of ways, depending on how theroughness or surface irregularity is configured. That is, in a preferredembodiment the surface roughness is formed randomly on the lenses ofpresent invention, and has no regular repeating patterns. The magnitudeof such random surface roughness could be measured in terms of actualpeak-to-valley dimension, but is typically quantified by its so-calledlight scattering level. The scattering level of any surface refers toits ability to scatter incoming light rather than directly transmit thatlight. Therefore, a surface with a scattering level of 100% does notdirectly transmit any light therethrough. In a preferred embodiment, theintraocular lenses of the present invention have partially opaque orroughened surfaces that have an 80% scattering level. Of course, othersurface configurations can produce such a magnitude of scattering. Themagnitude of the preferred random roughening is desirably visible to thenaked eye, and appears as a white, cloudy, or “frosted” surface. At aminimum, the roughening is desirably visible at an optical magnificationof 10×, but is more desirably visible to the naked eye.

The present invention contemplates economical manufacturing techniquesfor forming the roughened surfaces on intraocular lenses, especially formolded silicone lenses. Specifically, the mold used to shape the lenscan be left with a roughened surface which is then molded directly intothe periphery of the optic portion of the lens. In a preferredembodiment, the internal surface finish of the mold is formed byelectrodiode manufacturing (EDM) and has a finish of 70 rms, which is ameasure of roughness. Optic pins in the center of the mold form thesmooth optically refractive surfaces. Once the silicone lens is removedfrom the mold, it is essentially in finished form with the surfaceroughness remaining around periphery of the central optic. If the lensis made from a lathing process, the machine lines could be left on thelens and the machine line area masked off so that the opticallyrefractive portions can then be polished to shape. The machine linesfrom the lathe could be optimized during manufacturing to enhance theroughness.

While this invention has been described with respect to various specificexamples and embodiments, it is to be understood that the invention isnot limited thereto and that it can be variously practiced within thescope of the following claims.

1. An intraocular lens that reduces glare from incoming light rays tothe retina of an eye, comprising: fixation members adapted to fix theintraocular lens in the capsular bag of the eye; and an optic having ananterior face and an opposed posterior face, the optic being coupled tothe fixation members and defining: a light-transmitting portion centeredon a central optical axis and shaped to direct and focus light on theretina of the eye; and a periphery circumscribing the light-transmittingportion and defining the entire optic except for the light-transmittingportion, wherein the periphery includes anterior and posteriorperipheral regions on the anterior and posterior faces of the optic,respectively, and a peripheral edge that has, in sequence from theanterior peripheral region to the posterior peripheral region, ananterior convex portion adjacent the anterior peripheral region, apartial conical surface around the central optical axis, and cylindricalsurface around the central optical axis, and wherein the peripheral edgeand only the peripheral edge is partially opaque to the transmission oflight.
 2. The intraocular lens of claim 1, wherein the peripheral edgeof the optic is made of a light absorbing material.
 3. The intraocularlens of claim 1, wherein the light-transmitting portion of the optic isbi-convex.
 4. The intraocular lens of claim 1, wherein the peripheraledge has a peripheral corner located at a discontinuity between theperipheral edge and the posterior face for inhibiting cell growth ontothe optic.
 5. The intraocular lens of claim 1, wherein the peripheraledge is roughened so as to be partially opaque to the transmission oflight.
 6. The intraocular lens of claim 5, wherein the roughness of theperipheral edge is sufficient so as to be visible at a magnification of10×.
 7. The intraocular lens of claim 6, wherein the roughness of theperipheral edge has a scattering level of about 80%.
 8. The intraocularlens of claim 7, wherein the optic is molded and the roughness iscreated by the surface roughness of the mold.